A liquid crystal display panel is typically composed of a color filter substrate (CF substrate), a thin film transistor array substrate (TFT array substrate), and a liquid crystal layer disposed between the two substrates. Working principle of the liquid crystal display panel is that a driving voltage is applied to the two glass substrates to control rotation of liquid crystal molecules of the liquid crystal layer, and light from a backlight module is refracted to show a picture.
According to different orientations of the liquid crystals, liquid crystal display panels may be divided into a vertical alignment (VA) type, a twisted nematic (TN) type, a super twisted nematic (STN) type, an in-plane switching (IPS) type, and a fringe field switching (FFS) type. In a liquid crystal alignment of a conventional liquid crystal display panel, a voltage is applied to indium tin oxide electrodes at both ends of a liquid crystal cell. After the liquid crystals are arranged in regular order, the liquid crystal cell is irradiated with UV light, and a photosensitive monomer in the liquid crystals is polymerized onto a polyimide (Pl) surface for fixing orientation of the liquid crystal molecules on the PI surface. After the voltage is removed, the liquid crystal molecules on the PI surface form a pre-tilt angle to enhance response speed of the liquid crystal cell. When an optical alignment is performed in this manner, it is necessary to add a large number of wires onto the array substrate to provide the voltage to indium tin oxide on edges of the CF substrate, resulting in a decrease in utilization of the array substrate.